474 PHILIPPINE RODENTS CHAP. Sub-Fain. 2. Hydromyinae.—The genus Hydrowiys} of which there are several species, the best known being H. cfarysogaster, is an exclusively Australian form, and is aquatic in habit. It is a foot or so in length, and has a fairly long tail. The fore- and hind-limbs are webbed, in correspondence with its habits. The Australian Water-Bat is black, with an admixture of golden- coloured hairs dorsally and golden colour below, with a lighter median stripe. The thumb is small, and the webbing of the hands is not so marked as is that of the feet. The molars are only two in each half of each jaw. The caecum is rather small, the measurements of the alimentary canal being : small intestine, 895 mm.; large intestine, 278 mm.; caecum, 7 0 mm. Allied to the last is Xeromys, a genus which is also Australian, but limited to Queensland. It has been established by Mr. Thomas,2 who discovered that it has the same reduced formula as Hydromys. Xeromys, however, is not an aquatic animal, and has unwebbed feet. In the Luzon highlands Mr. Whitehead has discovered, and Mr. Thomas quite recently described,3 a number of peculiar Kodents. Of these the genera CJirotortiys> CelaenomySy and Cru- nomys are allied to the Australian and JSTew Guinea Hydromys. Ghrotomys whiteheadi is unusual among Muridae, in its coloration being marked by a pale stripe down the back. The creature is the size of the Black Eat (Mus rattus). It is terres- trial not aquatic in habit, in spite of its likeness to Hydromys. The molars, however, are ^. Orunomys fallow is more like Hydromys. It has, however, three molars, as in the last genus. But the skull has the flattened form characteristic of Hydromys as opposed to Mkts. lake SottotnySy Celaenomys silaceus is also somewhat inter- mediate between Hydromys and Mus. It is described as very Shrew-like in appearance, and has a very pointed muzzle. Its habits Mr. Whitehead is " quite unable even to guess at." Like Hydromys and Xeromys this Rodent has but two molars. Sub-Fam. 3. Bhynchomyinae.—The genus JZJiync'homys, con- taining but one species, Hh. soricioides (of Thomas), is also, as both Its generic and specific names imply, a somewhat Shrew-like form in external aspect. The skull, too, is Insectivore-like in its elonga- 1 For anatomy see Windle, Proc. Zool. Soc, 1887, p. 53. 8 JVoc. Zool. Sloe. 1889, p. 247. » Trans. Zool. Soc. xir. 1898, p. 377.